In the use of high boiling point solvent. Boiling point and evaporation rate, Custom Printed Flags Wholesale strictly speaking, is inconsistent. In Table 3-4 of the evaporation rate of ethyl acetate as 1, more than 1 digital, evaporation is faster than a digital slow. For example, xylene (0.7) 2.3 times faster than cyclohexanone (0.3), the evaporation rate.
Solvency of the solvent (solvent power), Table Flags For Sale the difference between the commonly used solubility parameter and hydrogen bonding index. The solubility parameter is the solubility of a system (solvents, resins) features, Custom Printed Flags Wholesale it is the square root of the adhesion of the system energy density. Hydrogen bond index, hydrogen bond strength index is used to describe the hydrogen bond strength. When the difference between the two is very small or the approximation of the two values, the solubility is good, otherwise poor; the difference is quite large, is not dissolved; in between, the occurrence of partial dissolution or bubble expansion. This analysis method, Desk Flags For Sale screen by the proper use of thinner, and analysis of adhesion fastness of the ink and the surface is useful.
Under normal circumstances, polarity a strong system (such as hydrogen bond generate system), if the the the the solubility of parameters of the two substances is similar to and the the hydrogen Kin-the case of the the same grade strength of O'clock, is expected to intermiscibility; non-(or weak) polar systems, as long as the solubility of the two substances is less than 1.5, can be compatibility. The solubility of the resin from the solvent, the solvent can be divided into active solvents, inert solvents and thinners, three kinds of. Active solvents dissolve the strongest; inert solvent, followed by; Personalised Football Flags thinner no dissolution of the resin, but can fight with the other two solvents mixed, dilute the effect.
Ink system, with the exception of the active solvent for the resin to get the best dissolution, taking into account the ink viscosity, evaporation rate, Wholesale Custom Printed Flags in addition to low-cost and improve the needs of a number of other characteristics, yet by adding inert solvents and thinners, so that of solvent components with the proper formula to obtain the balance of a variety of performance.
The ② additives. Pigment and links to materials commonly known as the main agent of the screen ink, ink, and a mixture of the single pigment and link material can not meet the diverse requirements of the silk screen process ink. So the ink will always be as additive as the additives used to improve the performance of the ink, adjust the appropriate ink.
Additives added to improve the ink adaptive auxiliary agent. Main defoamers, Custom Printed Flags Wholesale diluents, plasticizers, UV absorbers, dry adjustment agent.
Usually only when the of a small amount of additives, Wholesale Custom Printed Flags can make the of adaptive greatly improved.
a. Thickener. It can increase the material of the ink system scheduling. By the swap can reduce the settling of solid particles in the ink, to avoid the deposition of thin ink agglomeration: also change the rheology of the ink, the of fitness. By the swap in order to absorb the solvent and thickener, such as bentonite can absorb the water of 15 letter; some to Ink architecture mesh and thickening, such as mineral spirits, only 2% of the gas silicon Serve glue; some synthetic organic by the swap (thickener such as PTF), make the water increased deployment of 1,500 times, commonly used in thickening of the fabric paste (water-based ink).
and b. Less adhesive. From the main to improve the flow of ink and drawing of the role of Suitably increased less adhesive to improve the operation of ink adaptive image reproduction. However, if excessive addition, Custom Printed Flags Wholesale the uniformity of the ink will deteriorate, affecting reproduction.
(c) Desiccant. Promote the ink dry substance, Wholesale Custom Printed Flags also known as dry oil. Oxidation polymerization-type ink, the desiccant to join, make unsaturated double bonds of the material to accelerate the conjunctiva. College Flags For Sale Such desiccants are metal oxides, drier performance and metal type. Drilling dry oil is a reminder the fastest, and the surface to dry; manganese dry oil drier in general, the table at the same dry; lead dry oil drying slow drying from the inside and in the field.
(d) plasticizer. Additives, the ink film soft evaporation drying inks have a good effect, but adding too much will make resin softening, resulting in the adhesion of the substrate. No effect of plasticizers on the reactive ink. Nitrocellulose binders, inks often add dibutyl phthalate oil-based inks plus castor oil, glycerol in the water-soluble ink can improve them in some of the surface im fixation . The plasticizer is more common in the soft plastic screen . The selection of the plasticizer should be noted that the ink system compatibility and durability, the latter its volatile, the performance of the anti-migration resistance, lightfastness, heat resistance and cold resistance.
e. Defoamers. Including silicon and non-silicon systems. The former uses a wide range. Silicon defoamer has a good effect, but excessive use can cause ink adhesion adverse.
Bubble the elimination of two ways, one by a chemical reaction, such as acids and calcium salts can damage the soap film; another is the way to the top go into the foaming agents. The latter defoamer, the surface tension should be less than the surface tension of the foaming agent rarely dissolved in the ink, the surface of the spreading, and not enough to form a solid film. Defoamer also vary depending on the ink nature, such as water based inks often used octyl acetate, octanol, and glycerol; non-water-based ink is used tributyl phosphate. Polydimethylsiloxane (molecular weight 1200 to 2700) are two types of ink, the ink in the most widely used defoamers. Defoamer dosage should be strictly controlled, especially Gui oil defoamers, usually 3% of the ink.